Traditionally, commercial power from a utility has been used as the primary source of electrical power for a consuming entity, such as a telecommunications facility. Within such a facility is a wide variety of computing equipment such as switches, servers, routers, and other such devices. These devices, when in use, generate heat. This heat must be dissipated in order to avoid damage and possible malfunction of the computing equipment. As telecommunications equipment has advanced to include substantial amounts of digital equipment, maintaining sufficient climate control has become a greater concern to telecommunication providers, such that disruptions in telecommunication services caused by overheating are minimized.
The most common climate controlling approach utilized in the past has been to cool an entire telecommunications facility with an air conditioning system. Typically, this air conditioning system is powered by an existing alternating current (AC) power source, primarily AC drawn from a utility company.
A schematic diagram showing a typical prior art arrangement is shown in FIG. 1. Referring to the figure, an ordinary prior art system 110 includes an enclosed area, e.g., an entire facility, a room, or group of rooms, which includes a plurality of pieces of equipment 116 which are computing devices that generate heat. AC power is administered through an AC bus 132. To cool these devices and other equipment within a telecommunications facility, a building air conditioner 118 is provided that consumes AC from AC bus 132. Because the computing equipment 116 consumes DC, the AC must be converted to DC using a rectifier 130. The primary source of power to the system is received into bus 132 from an AC utility 114 from outside the facility. Also outside of the facility is a diesel generator 120 which is only active if the AC utility 114 has failed, e.g., in a blackout, or where a power line has been taken out of service. The third and final backup source is a plurality of valve-regulated lead-acid (VRLA) batteries 122 which are included in the DC circuit into which the equipment 116 is incorporated. The VRLA batteries must be stored inside the facility 112 because they cannot endure extreme temperatures.
This AC dependent prior art system has proved disadvantageous in the event both the utility and diesel generator sources of AC are unavailable. The VRLA batteries 122 may provide backup for a limited time, but the facilities air conditioning system cannot draw power from them because it runs on AC. Further, the DC power available from the VRLAs 122 cannot be inverted to power the air conditioning system because the load requirements of the air conditioner are too great.
Prior back-up power systems have been provided for telecommunications wherein only a portion of the back-up power is available for cooling the telecommunications and data devices. In such an arrangement, often times not all devices that require cooling can be cooled, since back-up power is also required for other facility operations.
These issues have caused operators to simply go without air conditioning and hope for the utility or diesel generator to come back on line before the temperature inside the facility reaches a level where the telecommunications and data equipment suffers heat-related damage. After that, if the AC sources are too late, the operator must decide whether to shut down, or endure equipment operational problems.